Many consumer electronics devices, such as desktop computers, laptop computers, and smart phones are becoming more compact. As these devices become smaller, the internal space available within their enclosure or housing for built-in loudspeakers becomes smaller as well. This is especially true as space within the device enclosure for speakers may compete with many other components such as circuit boards, mass storage devices, and displays. Generally, as a speaker decreases in size it is able to move less air mass and thus sound quality (or at least loudness) may decrease. This may be especially noticeable for sounds in the lower end of the audio spectrum, e.g. beneath 1 kHz. Furthermore, as the available open air volume within an electronic device shrinks, there is less air for a speaker to vibrate and thus limits the audible response. Similarly, the volume level and frequencies able to be produced by a speaker may also decrease as the size of the speaker decreases. Thus, as electronic devices continue to decrease in size, detrimental effects may be experienced for audio produced by the devices. Producing low frequency audio content (bass) out of thin consumer electronics devices is one of the most important problems in modern audio engineering.